Most presently known torches comprise a nozzle having a cutting orifice and a plurality of heating orifices. The cutting orifice serves to bring a flow of cutting oxygen to the workpiece, while the heating orifices enable the workpiece for cutting to be heated by burning a fuel gas in the heating oxygen. To illustrate the technological background, reference can be made to the following documents: DE-A-14 29 136, FR-A-444 349, DE-C-249 170, DE-B-12 09 973, and FR-E-9375. Reference can also be made to document U.S. Pat. No. 3 934 818 which shows an oxy-cutting torch fitted with a cooling system for spraying an air and water mixture of adjustable composition.
More recent techniques are illustrated in documents WO 96/18071 and WO 96/26806.
Although oxy-cutting methods using oxy-cutting torches are in widespread use in various stages of steelworking, it appears that the design and the materials used do not enable high precision to be obtained for machining purposes, even though ever greater precision is being required ever more frequently, and above all traditional torches continue to be tools that are fragile compared with their environment, which gives rise to high maintenance costs and to losses of production. In particular, torch nozzles are generally positioned relatively imprecisely on their supports which are generally made of copper, and such supports are moved frequently in operation, possibly with jolting. Consequently, the imprecise positioning, which deteriorates as use continues, gives rise to losses of throughput. When one or more nozzles are used simultaneously, these variations in positioning have an effect that is particularly harmful insofar as the various jets from the nozzles run the risk of interfering with one another, which naturally harms the efficiency of the action of such jets.